Possibly small drink? (4)
I believe the answer is:
beer
This clue could be a double definition.
'possibly small' is the first definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'drink?' is the second definition.
(beer is a kind of drink)
Can you help me to learn more?
(Other definitions for beer that I've seen before include "Drink flavoured with hops" , "Fermented alcoholic drink" , "Hopped drink" , "Perhaps bitter" , "Fermented alcoholic beverage" .)